CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
CONDENSED CONSOLIDATED BALANCE SHEETS
Receivables: allowance for doubtful accounts (in dollars)	$ 815	$ 714
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	68,000,000	68,000,000
Common stock, shares outstanding	47,739,024	41,908,218